Constant Lines in the U-V Plane

Highlights of the activity

• Students are placed into small groups and given two functions x and y which are both dependent on the variables u and v.
  1. Problem one: “Draw lines of constant u and v in the u-v plane.”
  2. Problem two: “Draw lines of constant x and y on the u-v plane.”
• Students will find that lines which were perpendicular in one coordinate system are not perpendicular in others.

Reasons to spend class time on the activity

We have found that many students have worked mostly with variables that are independent of one another. However, in thermodynamics, many of the variables are dependent on each other where changing one must change the other. This exercise helps students to visualize graphically that whenever dealing with thermodynamic variables, there is no sense in which those variables are perpendicular to (i.e. independent of) each other.

Reflections

• Reflections from the original implementation.

• Reflections from "official" adapters/adopters.

• Reflections from the general public.

Instructor's Guide

• Wiki version